The present invention relates to improvements in disposable diapers which enable the diaper to closely conform to the torso of a baby without causing any discomfort to the baby, while at the same time providing improved gasketing around the thighs and resultant fluid containment.
In the recent past disposable diapers have been introduced into the marketplace which have a narrow but relatively thick strip of elastic at each side thereof, so as to gather the side margins of the facing and backing layers of the diaper without gathering the absorbent panel thereof. Such diapers have an hourglass shaped absorbent panel, and are made generally in accordance with the teachings of U.S. Pat. No. 3,860,003. In order for the elastic members to be effective in such diapers, it is necessary that the elastic members be parallel with one another and spaced relatively far from the side marginal edges of the absorbent panel of the diaper, and for the elastic members to be associated with thin, highly flexible facing and backing layers. As a result, when such diapers are placed upon a baby, the narrow but relatively thick elastic members cause a narrow band of the facing layer to bear against the baby's skin with substantial line contact. This results in a high degree of stress concentration that may cause pinching and irritation of the baby's skin.
The problems attributable to the unduly high compressive force caused by such narrow but relatively thick elastic strips of the prior art diapers mentioned above are particularly acute when the baby has voided and the diaper is wet. Because the backing and facing layers are so highly flexible, when the diaper is wet and conditions are present tending to cause hydration of the baby's skin, the narrow elastic members sometimes cause the facing layer to press against the skin with sufficient force to injure the skin. Also, the elastic members in prior art diapers of the type described above cause the diaper to gradually creep upwardly upon the baby's thighs. As a result, the forces applied to the skin by the stressed elastic members increase the longer the diaper is worn.
Thus, the improved fit attributable to diapers having a contoured panel and elasticized side flaps is accomplished only with a sacrifice in comfort to the baby. This result is aggravated by having the elastic members parallel with one another, since such elastic members do not conform to the perineal area of the baby, and when the diaper is applied, higher pressures are applied to the inner sides of the baby's thighs.
While many attempts have been made in the past to provide diapers, both disposable and non-disposable, with improved fit characteristics without sacrificing comfort, heretofore such efforts have not met with success.